Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare a safe, closed read (readOnlyHint true, openWorldHint false), and the description adds behaviour the annotations do not: results are restricted to stocks with 5% large-holding or 1%+ executive/major-shareholder filings and are sorted by ratio descending. It also explains that value is disclosed share count times the latest close price, total_value is the sum, and that total above shown means raising limit will return more — useful detail beyond structured fields, though unit/currency of the ratio and update freshness are unstated.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is front-loaded with what the tool returns and the reporting filter, then moves to parameter caveats, then to output semantics. Every sentence carries information; density is high but nothing is filler, and the caveat about partial names is placed where it matters.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

There is no output schema, so explaining value/total_value/total-versus-shown in the description is exactly the right compensation, and the reporting-threshold caveat prevents over-reading the list as complete ownership. Only min_ratio's meaning and the treatment of include_indirect's effect on ratios are left to inference.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 80%, so the baseline is 3, but the description adds real meaning: it identifies entity_id as coming from search_holder and scopes it to a single holder, and explains the ambiguity risk of the holder name parameter and the limit/total interplay. Only min_ratio is left unexplained in both schema and description.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The opening sentence names a specific verb and resource (the list of stocks held by a holder, with ownership ratios, sorted by ratio descending) and states the reporting threshold that limits which stocks qualify. It is clearly distinguishable from the holder-listing or history siblings, though it never names those siblings explicitly.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It states the default holder (국민연금) and recommends passing entity_id from search_holder, warning that a partial 'holder' name can mix in other same-named holders and unconfirmed reports. That is concrete when-to-use and when-to-prefer-an-alternative guidance, though it does not say when to use a sibling such as get_holders instead.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.